Maximum Impact

Thursday, January 10, 2013

In addition to external beam radiation therapy (EBRT), which directs radiation at a tumor from outside the body, Baptist specialists are also using high-dose rate (HDR) brachytherapy to deliver radiation inside the body via catheters placed near a tumor. HDR brachytherapy is most frequently used for gynecologic malignancies and sometimes breast, prostate and other types of tumors.

“For high-dose rate brachytherapy, small catheters are placed inside the patient in the location to be treated,” explains Margaret Wadsworth, MD, a radiation oncologist at Baptist and a partner with Radiation Oncology of Mississippi in Jackson. “A CT scan of the area is done, which allows the physician and physicist to create a computer plan showing where the radiation dose should be aimed and how much dose should be delivered. Then a tiny radioactive source is inserted and allowed to stay at certain positions in the catheter for a precise number of seconds to deliver the planned amount of radiation in the desired location. Delivering brachytherapy safely and effectively requires significant support from a physicist, so not all radiation oncology centers are able to offer this treatment.”

Generally, fewer visits are required than with external beam radiation therapy because a higher dose is delivered with each treatment, says Wadsworth.

“After surgery, brachytherapy alone can be used to treat some early-stage endometrial cancers to decrease the risk of recurrence,” she says. “This involves about a 1-hour procedure once a week for three weeks. Some patients with higher-risk endometrial cancers need treatment with external beam radiation therapy to target regional lymph nodes. Sometimes, HDR brachytherapy is still used to give additional dose to the vaginal cuff, a common site of cancer recurrence.”

Brachytherapy is a crucial part of treatment for locally advanced cervical cancers, Wadsworth emphasizes.

“For cervical cancer, daily external beam radiation therapy is usually started first, along with weekly chemotherapy,” she says. “Brachytherapy treatments are given near the latter part of or after external beam radiation therapy. In the past, low-dose rate brachytherapy was used, which required hospitalization for several days with a radioactive source placed inside the patient, steadily delivering radiation. Now, HDR brachytherapy is available, which delivers an equivalent dose of adiation in treatments of 10 to 15 minutes, usually given four or five times. Conscious sedation or general anesthesia is still needed for comfort during insertion of the applicators. But a radioactive source only enters the patient for the 10- to15-minute treatment and the patient can return home the same day.”

HDR brachytherapy treatment instead of traditional therapy definitely improves the quality of life for women with cervical cancer, says Jimmy Moore, MD, a gynecologic oncologist at The Women’s Specialty Center in Jackson. “With traditional therapy, a metal apparatus was implanted with packing to insure it stayed in place for several days,” explains Moore. “Patients were confined to their hospital bed during that time and couldn’t raise the head of their bed more than 30 degrees.The necessary immobility during conventional brachytherapy increased the risk of blood clots.”

HDR brachytherapy is now delivered with a much less cumbersome device and very little packing. The device is easily removed when the patient goes home, Moore adds. “There’s less pain, less pressure,” he says. “This is a much lessdebilitating treatment for women with cervical cancer.”

For more information log onto http://mbhs.org/cancer or call (601) 968-1049.